The U.S. Food and Drug Administration (FDA) has approved Tasigna (nilotinib) capsules for treatment of Philadelphia chromosome positive chronic myeloid leukemia (CML) in adult patients whose disease has progressed on or who cannot tolerate other therapies that included imatinib. Imatinib (Gleevec) is approved for the treatment of new diagnosed patients with Philadelphia chromosome positive CML.

FDA’s approval of Tasigna includes a black box warning for possible life-threatening heart problems that may lead to an irregular heartbeat and possible sudden death.

CML accounts for 15 percent of all leukemias in adults. Approximately 4,500 new cases of CML will be diagnosed in 2007. An abnormal chromosome, called the Philadelphia chromosome, is located in the leukemic cells and is present in the majority of CML patients.

“This represents another treatment option for CML patients who are resistant to or can no longer tolerate imatinib,” said Janet Woodcock, M.D., FDA’s deputy commissioner for scientific and medical programs, chief medical officer and acting director, Center for Drug Evaluation and Research. “Patients should consult with their physicians, however, because of possible life-threatening heart problems associated with this drug.”

The effectiveness of Tasigna is based on response rates observed in an ongoing clinical trial. Responses are associated with normalization of blood counts and bone marrow examinations. Further follow-up of patients is needed to determine how long these responses will last.

Patients may lower their chances for the heart problems by taking Tasigna without food, and by avoiding grapefruit products. Patients should also consult with their physician or other health care professional about avoiding other medications that can cause heart problems when taking Tasigna.

Patients with low blood potassium or magnesium should not use Tasigna.

The most common side effects include low blood counts, rash, headache, nausea and itching. Other possible serious side effects include liver damage, fluid accumulation and pancreas inflammation.

Women are advised to avoid becoming pregnant while taking Tasigna. Women who become pregnant are advised that Tasigna can harm their unborn child. Nursing mothers are advised not to breastfeed their child while taking the drug.

Tasigna is manufactured by Novartis Pharmaceuticals Corporation, East Hanover, N.J.